// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_WEBSOCKETS_WEBSOCKET_MANAGER_H_
#define CONTENT_BROWSER_WEBSOCKETS_WEBSOCKET_MANAGER_H_

#include <set>

#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/timer/timer.h"
#include "content/browser/websockets/websocket_impl.h"
#include "content/common/content_export.h"
#include "net/url_request/url_request_context_getter.h"
#include "net/url_request/url_request_context_getter_observer.h"

namespace content {
class StoragePartition;

// The WebSocketManager is a per child process instance that manages the
// lifecycle of WebSocketImpl objects. It is responsible for creating
// WebSocketImpl objects for each WebSocketRequest and throttling the number of
// WebSocketImpl objects in use.
class CONTENT_EXPORT WebSocketManager
    : NON_EXPORTED_BASE(public WebSocketImpl::Delegate),
      NON_EXPORTED_BASE(public net::URLRequestContextGetterObserver) {
public:
    // Called on the UI thread:
    static void CreateWebSocket(int process_id, int frame_id,
        blink::mojom::WebSocketRequest request);

    // net::URLRequestContextGetterObserver implementation.
    void OnContextShuttingDown() override;

protected:
    class Handle;
    friend class base::DeleteHelper<WebSocketManager>;

    // Called on the UI thread:
    WebSocketManager(int process_id, StoragePartition* storage_partition);

    // All other methods must run on the IO thread.

    ~WebSocketManager() override;
    void DoCreateWebSocket(int frame_id, blink::mojom::WebSocketRequest request);
    base::TimeDelta CalculateDelay() const;
    void ThrottlingPeriodTimerCallback();

    // This is virtual to support testing.
    virtual WebSocketImpl* CreateWebSocketImpl(
        WebSocketImpl::Delegate* delegate,
        blink::mojom::WebSocketRequest request,
        int child_id,
        int frame_id,
        base::TimeDelta delay);

    // WebSocketImpl::Delegate methods:
    int GetClientProcessId() override;
    StoragePartition* GetStoragePartition() override;
    void OnReceivedResponseFromServer(WebSocketImpl* impl) override;
    void OnLostConnectionToClient(WebSocketImpl* impl) override;

    void ObserveURLRequestContextGetter();

    int process_id_;
    StoragePartition* storage_partition_;
    scoped_refptr<net::URLRequestContextGetter> url_request_context_getter_;

    std::set<WebSocketImpl*> impls_;

    // Timer and counters for per-renderer WebSocket throttling.
    base::RepeatingTimer throttling_period_timer_;

    // The current number of pending connections.
    int num_pending_connections_;

    // The number of handshakes that failed in the current and previous time
    // period.
    int64_t num_current_succeeded_connections_;
    int64_t num_previous_succeeded_connections_;

    // The number of handshakes that succeeded in the current and previous time
    // period.
    int64_t num_current_failed_connections_;
    int64_t num_previous_failed_connections_;

    bool context_destroyed_;

    DISALLOW_COPY_AND_ASSIGN(WebSocketManager);
};

} // namespace content

#endif // CONTENT_BROWSER_WEBSOCKETS_WEBSOCKET_MANAGER_H_
